The National Wild and Scenic Rivers Act was an outgrowth of the recommendations of a Presidential commission, the Outdoor Recreation Resources Review Commission (ORRRC). Among other things, the commission recommended that the nation protect wild rivers and scenic rivers from development that would substantially change their wild or scenic nature. The act was sponsored by Sen. Frank Church (D-Idaho) and signed into law by PresidentLyndon B. Johnson on October 2, 1968. A river or river section may be designated by the U.S. Congress or the Secretary of the Interior. As of July 2011[update], 203 rivers, totaling 12,598 miles of river in 38 states and Puerto Rico, have wild and scenic status.[1] By comparison, more than 75,000 large dams across the country have modified at least 600,000 miles, or about 17%, of American rivers.

Selected rivers in the United States are preserved for possessing outstandingly remarkable scenic, recreational, geologic, fish and wildlife, historic, cultural, or other similar values. Rivers, or sections of rivers, so designated are preserved in their free-flowing condition and are not dammed or otherwise impeded. National wild and scenic designation essentially vetoes the licensing of new hydropower projects on or directly affecting the river. It also provides very strong protection against bank and channel alterations that adversely affect river values, protects riverfront public lands from oil, gas and mineral development, and creates a federal reserved water right to protect flow-dependent values.

Designation as a wild and scenic river is not the same as a national park designation, and generally does not confer the same level of protection as a Wilderness Area designation. However, wild and scenic designation protects the free-flowing nature of rivers in non-federal areas, something the Wilderness Act and other federal designations cannot do. Designation does not alter property rights.

Federally administered National Wild and Scenic rivers are managed by one or more of the four principal land-managing agencies of the federal government. Of the 156 National Wild and Scenic Rivers, the most are managed by the U.S. Forest Service, followed by the National Park Service. Thirty-eight are managed under the Bureau of Land Management's National Landscape Conservation System while the U.S. Fish and Wildlife Service manages several rivers in Alaska.

State-managed wild and scenic rivers are subject to the same protections as federally administered rivers. These state rivers are added to the National System by the Secretary of the Interior following an application by the governor of the state the river flows through.

Wild and scenic rivers are assigned one or more classifications: wild, scenic, or recreational. These classifications are based on the developmental character of the river on the date of designation. Wild rivers are the most remote and undeveloped while recreational rivers often have many access points, roads, railroads, and bridges. A river's classification is not related to the value(s) that made it worthy of designation and that must be protected and enhanced by the river manager. For instance, recreation may not be an outstanding value on a river with a recreational classification nor scenery on a river classified as scenic. Notably, wild and scenic rivers receive the same standard of protection regardless of classification.